This invention relates to a system of building construction with modules consisting of factory-built, custom-assembled units, and more specifically to prefabricated concrete form-work modules that can be assembled together to construct walls, floors and ceilings with minimal on-site labor.
The use of concrete as a construction material offers several advantages over the use of conventional wood and masonry materials due to its higher strength and resistance against the natural elements. For example, concrete structures are more resilient against decay, insect attacks, earthquakes, extreme winds and water damage.
Concrete form-work modules have been utilized for casting concrete structures. In these construction systems, insulated, composite walls formed of a concrete core and covered with sheet material have been produced by using the sheets to form molds for casting the concrete. This is done by pouring concrete between a pair of parallel, spaced sheets, which provide a mold for the concrete. The sheets and the concrete form a composite wall when the concrete is cured.
In most instances relating to this type of construction, the form-work modules must be assembled or modified on the premises. This on-site effort often requires the use of special tools and skilled labor as well as extra time, resulting in additional cost in order to complete the construction project. Furthermore, the sheets used in these systems are often overlaid with finished decorative paneling that is not capable of repeated disassembling and reassembling to the form-work module.
U.S. Pat. No. 4,698,947 issuing to McKay on Oct. 13, 1987 discloses a concrete wall form tie system used for aligning and positioning sheet-forming panels, immobilizing the panels against movement due to hydrostatic pressures of the concrete, and serving to better resist and dissipate any undue heat applied to wall construction. The wall form tie system comprises a pair of foamed plastic sheets with concrete poured into the space between the foamed plastic sheets to make a composite wall. An exterior wall covering formed of gypsum board or other construction material may be applied to either or both of the exposed surfaces of the foamed plastic sheets.
U.S. Pat. No. 6,070,380 issuing to Meilleur on Jun. 6, 2000 discloses a concrete wall formwork module that can be assembled with other identical modules like a brick wall to form a mold into which concrete is poured. Once assembled and filled with concrete, the modules are left in place providing a concrete wall with panels on both sides of it. The concrete wall formwork module comprises a reinforcing structure preferably made of parallel grids connected by transverse tie-rods, a pair of opposite panels forming spaced apart longitudinal side-walls, concrete poured between the foam panels, and arms defining a bridge for providing stability between adjacent modules when assembled to form a wall.
U.S. Pat. No. 4,762,453 issuing to DeCaro on Aug. 9, 1988 discloses a helical coil fastener for securing insulation or other material to a roof deck.
U.S. Pat. No. 4,616,455 issuing to Hewison on Oct. 14, 1986 discloses fastening assemblies for fastening compressible insulation material onto a roof decking.
It is therefore an object of the invention to provide a system of building construction comprising prefabricated modules that can be assembled with other similar and compatible modules to construct reinforced concrete-steel walls, floors and ceilings.
It is also an object of the invention to provide a system of building construction comprising prefabricated modules requiring an absolute minimum of on-site labor for assembly.
It is also an object of the invention to provide a system of building construction comprising prefabricated modules with wall sections having finished paneling that may be repeatedly disassembled and reassembled without significant wear on the modules.
In the broader aspects of the invention, the system of building construction comprises prefabricated modules with wall sections having finished paneling on both faces, inner panels and separators made from insulating foam, such as expanded polystyrene (EPS), and a steel-reinforced concrete core. The modules come complete with the outer and inner finished panels as well as the inner insulating foam so that no on-site mounting of the panels and foam is required. Additionally, the modules require very little labor for assembly since they are attached to each other on-site with simple screws to create a complete wall system. Concrete is subsequently poured into the module cores to create a monolithic structure with a concrete floor or foundation. Inner-wall gypsum board, or any other wood or composition paneling, is already in place and needs only to be decorated as desired. Similarly, the external panels, which also may be of any type of wood or composition paneling, are ready for finishing. All elements stay in place and no forms or heavy external bracing need to be placed or removed.
Since the factory-built modules may be attached to each other on-site with simple hand tools with relatively unskilled labor, and since they require almost no on-site modifications or special tools, the system of the present invention is well adapted to the efforts of Do-it-yourself enthusiasts and small general contractors.
The modules are held together in a sandwich configuration by unique wire elements called xe2x80x9ccoiliesxe2x80x9d. The outer and inner: finishing panels and the interior foam panels and foam spacers of the modules are held in place by the coilies before concrete is poured. Since the facing panels and inner foam panels are not bonded with adhesive, they may be removed, replaced or remounted at any time in the future. Small depressions, or bosses, in the foam panels allow concrete to flow around the coiled ends of the coilies, so that after the concrete cures, the coils become embedded in the concrete, while the coiled wire ends become threaded inserts for standard screws. Consequently, the panels may all be disassembled and reassembled many times, e.g. repair after fire or flood, or simply to redecorate after long use, without significant wear to the imbedded coilies or screws.
The coilie and its use are one of the most unique and novel aspects of the present invention since other foam/concrete wall systems require on-site drilling of holes in sheet metal or plastic pieces inserted in the foam blocks to attach wall panels. In these systems the sheet-metal screws used can be removed and replaced only once or twice before the hole threads are stripped. Even at best the withdrawal force for sheet-metal screws is low (perhaps 50 to 200 pounds) depending on whether they are screwed into metal or plastic. Furthermore, in other systems the screws are not embedded in concrete at all. Since in the present invention the coilies are embedded in the concrete wall, they permit almost unlimited removal and replacement of the screws without significant wear while maintaining a minimal removal force of over 1000 pounds.
In addition to the wall system described above, a related and compatible reinforced concrete floor/ceiling system is also a part of the modular array. The floor/ceiling modules also have pre-placed facing panels and foam-panel constructions with coilies which permit the creation of a reinforced concrete floor/ceiling which has integral cast reinforced beams and which is tied by reinforced concrete to the wall modules. All previously described features carry over into the ceiling/floor system.
The above-mentioned and other features and objects of the invention and the manner of attaining them will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings wherein: